1. Field of the Invention
The invention relates to treating heart disease, and more particularly systems, devices and methods for reestablishing or improving blood flow to the myocardium.
2. Description of Related Art
Despite the considerable advances that have been realized in cardiology and cardiovascular surgery, heart disease remains the leading cause of death throughout much of the world. Coronary artery disease, or arteriosclerosis, is the single leading cause of death in the United States today. As a result, those in the cardiovascular field continue the search for new and improved treatments.
Coronary artery disease is currently treated by interventional procedures such as percutaneous transluminal coronary angioplasty (PTCA), atherectomy and coronary stenting, as well as surgical procedures including coronary artery bypass grafting (CABG). The goal of these procedures is to reestablish or improve blood flow through occluded (or partially occluded) coronary arteries, which is accomplished, for example, by enlarging the blood flow lumen of the artery or by forming a bypass that allows blood to circumvent the occlusion. What procedure(s) is used typically depends on the severity and location of the blockages. When successful, these procedures restore blood flow to myocardial tissue that had not been sufficiently perfused due to the occlusion.
Technological and procedural advances have improved the results obtained by the medical procedures now used to treat heart disease, and in particular coronary artery disease. There is, however, still much room for improvement. For that reason there remains a need in the art for new and improved systems, devices and methods for treating heart disease such as arteriosclerosis.
In one embodiment, the invention provides a device for delivering a conduit into the wall of a patient""s heart to place the conduit in communication with a heart chamber. The device includes a support member, a conduit disposed on the support member, and a sheath overlying at least a portion of the conduit. The sheath is moved to expose a portion of the conduit upon positioning the support member and conduit at a desired location within the wall of the heart.
In another embodiment, the invention provides a device for delivering a conduit to a selected location in the wall of a patient""s heart to place the conduit in communication with a heart chamber. The device includes a support member, a conduit disposed on the support member, and a positioning member configured to engage tissue so as to place the conduit in a selected position within the heart wall. The positioning member is disposed a predetermined distance from the conduit. The position of the conduit relative to the heart wall is determined by the location of the positioning member relative to the heart wall.
In another embodiment, the invention provides a device for delivering a conduit through the wall of a patient""s heart and the wall of a coronary vessel to communicate a heart chamber with the coronary vessel. The device includes a support member configured for placement through the wall of a heart into a heart chamber, and an expandable conduit sized and configured for placement in the heart wall so as to communicate the heart chamber with a coronary vessel. The conduit is supported on the support member in a collapsed orientation and moved to an expanded orientation by an expansion mechanism on the support member.
In yet another embodiment, the invention provides a method for placing a conduit in the wall of a patient""s heart. The method includes providing a support member and a conduit, passing the support member and the conduit through a wall of a coronary vessel and through the wall of a patient""s heart, positioning the conduit within the wall of the heart, and removing the support member and leaving the conduit in the wall of the heart.
In another embodiment, the invention provides a method for placing a conduit in the wall of a patient""s heart at a selected position with respect to the heart wall. The method includes providing a support member and a conduit, the support member having a positioning member disposed at a predetermined location with respect to the conduit. The support member and conduit are passed through a wall of a coronary vessel and through the wall of a patient""s heart, and the positioning member is located against tissue to place the conduit at a selected location within the wall of the heart. The support member is removed leaving the conduit in the wall of the heart.
In still another embodiment, the invention provides a method for placing and expanding a conduit in the wall of a patient""s heart. The method includes providing a support member and a conduit, the conduit being supported in a collapsed orientation and movable to an expanded orientation. The support member and the conduit are placed in the wall of a patient""s heart, the conduit is expanded and the support member is removed while leaving the conduit in the wall of the heart.
In yet another embodiment, the invention provides a device and method for forming a channel that extends at least partially through the wall of a patient""s heart and communicates with a heart chamber. This embodiment includes a shaft and a tissue removal mechanism movably supported on the shaft. The tissue removal mechanism including a tissue-removing portion that is actuated to remove a section of tissue from a patient""s heart to form a channel that extends at least partially through the heart wall and communicates with a heart chamber. A conduit may be placed in the channel to form a blood flow path or the channel itself may form the path.
In another embodiment, the invention provides a device and method for removing a portion of the wall of a coronary vessel located adjacent the wall of a patient""s heart. This embodiment includes a shaft and a tissue-removing mechanism disposed at a predetermined distance with respect to the shaft. The shaft is placed adjacent the wall of a coronary vessel and the tissue-removing mechanism is positioned against the wall of the coronary vessel. An actuator coupled to the tissue-removing mechanism is actuated to remove a portion of the wall of the coronary vessel without removing a substantial portion of the wall of the heart located adjacent the coronary vessel.
In another embodiment, the invention provides a device and method for forming a channel through at least a portion of the wall of a patient""s heart by utilizing electrical energy. This embodiment includes a shaft and an electrode disposed adjacent a distal end of the shaft. The electrode is adapted to apply electrical energy to tissue in order to ablate the tissue and is coupled to a source of electrical energy, preferably RF (radiofrequency) energy.